What if the fantastic four turned against each other and battled, who would win.
"Probalby Sue! She could incase them in her forcefield and thats that!"
The issue with the force field is that she can't keep it up all day. She'll tire eventually. Especially with the Thing in there. But I'm not arguing with you that she would win.
IW has performed multiple activites on many occasions.
In this case, she could be invisible and simply enlarge a force bubble in the heads of the Thing and HT, who are both susceptible to this kind of attack.
I don't think that this would kill Mr F due to the nature of his powers but she can project thin lines of force capable of cutting him as displayed when she was possessed by Malice.
As for HT's Nova Blast. If IW lets the blast wve roll over her, with a force field cover, she will not encounter the entire effects of the 'force' created.
She may be able to sustain the forcefield in this case.
Overall, she has the best chance to win.
Sue with Reed a close contender. She has been shown to redirect the force of a nuclear blast so the Thing and Torch cant do nada, the only one to worry about would be Reed because of that brain of his. He probably has his version of the Xavier protocols on them so has some kinda failsafe ways to kill them all.